While 2016 has been a career year for Belt so far, it's not like these results have come out of nowhere. The 28-year-old hit .289/.360/.481 with a 140 wRC+ in 2013, and .280/.356/.478 with a 135 wRC+ last year, sandwiched around an injury-shortened '14 campaign.
Yet Belt has made some impressive strides at the plate, helping him put up a .301/.412/.514 line through Tuesday, when a pitch hit him on the right foot (X-rays were negative, though Belt didn't play on Wednesday).
A season ago, Belt walked in 10.1 percent of his plate appearances and struck out 26.4 percent of the time, which in both cases was close to his career norms. In 2016, both numbers have moved dramatically in a positive direction.
Belt's 15.6-percent walk rate and 16.4-percent strikeout rate give him 0.95 walks-per-strikeout which ranked 10th best among qualified hitters as of Wednesday. He finished 88th in that category last year, at 0.38.
During Belt's 24-game on-base streak, which ended May 17, Giants manager Bruce Bochy credited Belt for making "a lot of improvement with his pitch selection." The numbers back up Bochy's assertion, helping to explain how Belt has managed to boost his walks while slashing his whiffs.
To drastically oversimplify things, a key for any hitter is to swing at strikes and not at balls. Of course, that is much easier said than done, but Belt has been better at it this year than just about any other hitter.
Belt has offered at only 22.7 percent of pitches outside the strike zone, according to FanGraphs, which was the 22nd-lowest rate among qualified hitters entering Wednesday, and an improvement from last year's 28.6 percent. Meanwhile, his in-zone swing rate has ticked up slightly, to 82 percent, which trailed only the Orioles' Jonathan Schoop.
No hitter has a larger gap between those two numbers.
Earlier this season, Belt told the San Francisco Chronicle that last September, just before suffering a season-ending concussion, he made a crucial mechanical adjustment at the plate. By carrying that over to this year, he has been able to track pitches for longer before deciding whether to swing.
"I'm back to seeing the ball, not guessing," Belt told the Chronicle. "The results are not very good when I guess. For a few years, I was just searching for something to hold on to. I think I've found it."
Whatever the reason behind it, Belt has become a much more disciplined hitter, and not coincidentally, one of the very best in baseball so far in 2016.
Andrew Simon is a reporter for MLB.com. Follow him on Twitter @AndrewSimonMLB. This story was not subject to the approval of Major League Baseball or its clubs.